1. Field of the Invention
The present invention relates to optical disc devices, and, in particular, to an optical disc device capable of reproducing a hybrid optical disc in which a DVD layer and a next generation DVD layer are arranged in a stacking direction.
2. Description of the Related Art
Presently, standardization of the next generation DVD (Digital Versatile Disc) using a blue laser light having a wavelength of 405 nm is being put forward. In such standardization, consideration is being made on arranging two recording layers, which are the recording layer (hereinafter referred to as “HDDVD layer”) corresponding to the blue laser light and the recording layer (hereinafter referred to as “DVD layer”) corresponding to the red laser light, in the stacking direction.
In the next generation DVD (hereinafter referred to as “hybrid next generation DVD”), it is assumed that a video content is recorded on the large capacity HDDVD layer in the high-definition (HD) mode, and the same content is recorded on the DVD layer in the standard (SD) mode. In such a case, particularly strict copyright protection is required for the video content of HD mode recorded on the HDDVD layer.
Japanese Laid-Open Patent Publication No. 2003-346348 described below discloses an optical disc with two recording layers and a drive unit for the same.
In the drive unit for reproducing the hybrid next generation DVD, consideration is made on which of the DVD layer and the HDDVD layer should be given the priority in reproduction over the other. Here, a method of giving the priority to and reproducing the HDDVD layer having a greater capacity may be used as one method.
However, this may pose a risk that, if the copyright protecting function of a monitor to which the device is connected is not sufficient, the video content of HD mode recorded on the HDDVD layer is illegally retrieved through the monitor. In a case where the connected monitor is not adaptable for the HD mode, the possibility of the video content of HD mode being exposed to illegal copy increases if the HDDVD layer is unnecessarily reproduced. Therefore, when the connected monitor is inadaptable for the HD mode, reproduction of the video content of HD mode is not necessary, and it is sufficient to reproduce the video content of SD mode of the same content recorded on the DVD layer.